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hessian writes "New measurements suggest the Earth's inner core is far hotter than prior experiments suggested, putting it at 6,000C — as hot as the Sun's surface. The solid iron core is actually crystalline, surrounded by liquid. But the temperature at which that crystal can form had been a subject of long-running debate. Experiments outlined in Science used X-rays to probe tiny samples of iron at extraordinary pressures to examine how the iron crystals form and melt."

Let's be fair, my phrasing was ambiguous. There is a viable reading of what I posted that makes it look like I was implying what he said I was. I wasn't, but it is my fault for being insufficiently clear that I meant it as an example, not a universal assertion.

Not really true, if you go back far enough. At least, not in the way modern discrimination and racism works. Otherwise you're going to be hard pressed to explain how Macrinus (a Berber and not even a senator) came to power in Rome in 217. Or why Christian slaves in 1200 could easily be freed when they converted - which would not have been possible if they were enslaved because of their skin.

The whole concept of "race" is a modern construct, easily traced back to the times when slaves were used on plantation

No, the core is not hot enough to sustain fusion. 6000 degrees is not enough for fusion. Not in the earth's core, not on the surface of the sun either. The sun doesn't do fusion on the surface. It does fusion deep inside, where the temperature is millions of degrees. The earth and the sun have one thing in common - both are much hotter inside than on the surface. . .

It was a big idea for several years up until 2007 or so - at that pressure, an iron crystal will reject impurities. I guess the fact that nickel-iron alloy is heavier than elemental nickel or iron meant there was never a chance for that crystal to form.

Actually, very few thought the world was flat even before Christianity.

Anyone who has sailed, knew it wasn't.

The issue was, we all thought Columbus was crazy because everyone thought the earth was bigger and he would die at sea (and you know what, we were right....neener neener -just happened there was a whole 'nother continental mass in between).

The new estimate is "plus or minus 500C". Sounds like they had a coarse number (guessing plus or minus one or two thousand) and now they have a slightly more accurate number. Certainly no need for sensationalistic headlines.

Not all "20%"'s are created equal. For instance, if the temperature outside increases from 5C to 6C, you probably don't even notice. If it goes from 35C to 42C, you probably are rather unhappy about that.

Not all "20%"'s are created equal. For instance, if the temperature outside increases from 5C to 6C

5C to 6C is less than a 1% increase in temperature.

(Celsius isn't a ratio scale where 0 of the quantity measured is 0 on the scale; Kelvin is -- 5C to 6C is 278K to 279K; at the range of 5000C to 6000C, the difference between C and K is small and doesn't effect ratios much, but at 5-6C that's not true.)

Semantics, yes, but you can't grade "hotness" on either the Fahrenheit or Celsius scales by a percentage; otherwise 1 degree is infinitely "hotter" than 0 degrees!

To be fair, in Kelvin this is a 19% increase, so the semantic difference seems irrelevant. To put it in perspective, though, a 20% increase from room temperature (25 C or 298 K) would be 85 C (358 K); I'm pretty sure you'd agree that's "far" hotter!

How about an anthropic "hotness" unit on a scale from the sea level freezing point of the most abundant compound in the human body (oxidane, freezes at 0 C, triple point a tiny fraction of a kelvin higher) to the normal operating temperature of the human body (37 C)?

So basically, you heat up a small sample and put it under extreme pressures, and measure the electrical conductivity until it resembles the earth. Of course, there's a massive temperature gradient from the lab-temperature edge of the sample and the superhot center. And maybe the sample's gonna be at different temperatures as well, developing grain boundaries in the sample, and maybe those grain boundaries will serve as circuits around the superhot center of the sample.

I'm a long way off being a geologist but is it possible that the pressure on the solid core is so great that it becomes some state anagolous to a carbon diamond - but for Iron, hence an Iron Diamond. It's strange to think of the molten Iron around the solid core as a lubricant for the rest of the crust above and the core below it but maybe that's what it takes to apply that pressure and create that state of Iron Diamond.

I don't know - I'm just putting it out there and it's probably already been thought of,

... This is not an important issue, as your question is about crystallography, not geology. I'm not a crystallographer, but I did enough of it (up to reading X-ray diffraction results for mineral identification, and quite a lot of symmetry work, also for mineral identification) to recognise which field your question applies to. (I am a geologist ; card-carrying, along with an uncut diamond. Diamond is a fascinating material and mineral - why do people ruin it by polishi

Given the orders of magnitude and error bars involved and that the temperature at the core is all theory in the first place, ice-cold is far to precise.

Just use absolute-zero cold.

The temperature of the surface of the sun is smaller than the error bounds on our theories about the the temperature of the core. Thus if you are comparing them you might as well treat the surface temp as 0 and save a subtraction...

Unless, of course, the comparison is based on ratio (division) rather than subtraction, which is quite reasonable -- after all, we use logarithmic scales quite often, and human senses are generally logarithmic in terms of perception, which makes it all the more intuitional.

There are many problems and that certainly is one of them. Why we're funding people to have kids that they don't bother to raise is an important issue. BUT, there are also a lot of parents who have no choice but to send kids to horrible schools. Private education is way outside their budget. With AI tutors we can see "day cares" provide a quality education. The "day care" is there to deal with socialization and scheduling the AI provide one-on-one tutorship in all and every subject.

But most people who vote for politicians and who support such policies do not do so for that reason - at least not consciously. They want to be "kind" and "compassionate" and don't see another way that isn't "mean-spirited."

I'm at a loss for how to explain how counter-productive their policies are.

Don't you mean "the number one problem in US education, parents who have to both work 12 hours a day leaving them no time to raise their children"?. Personally I've only been a successful parent due to having an order of magnitude cheaper housing compared to the going rate, thank deity.

Actually it is possible to get a great education in the US. Most don't because the system is set up to encourage you to just do enough to get by. If, however, you are highly motivated and or have parents that encourage and demand that you strive for the best then you can go far indeed. The problem is that the average are left in the dirt.

I am no physicist, so, what impact does this have on the estimated age of the earth?

None.

Around half of the Earth's internal energy is from radiogenic sources (potassium, uranium and thorium decaying in the interior) and about half is the heat of accretion (landing comets and asteroids on the surface supplies a lot of energy). A relatively small (20%) change in estimated internal temperature doesn't affect the estimate of the age of the Earth, because the age of the Earth is not estimated from it's tempera